/* Shared site header, nav dropdowns, mobile menu, footer — load after page-specific styles */
:root {
  --surface2: #f0f3fc;
  --border: #e2e7f5;
  --text2: #334155;
  --muted: #64748b;
  --muted2: #94a3b8;
  --accent: #4f46e5;
  --accent-h: #4338ca;
  --accent-lt: #eef2ff;
  --radius: 18px;
  --header-bg: rgba(255, 255, 255, 0.95);
  --dropdown-bg: #ffffff;
  --footer-bg: #0f172a;
  --header-height: 68px;
  --sidebar-width: 280px;
  --content-max: 1400px;
  --content-mid: 900px;
}
:root[data-theme="dark"] {
  --surface2: #263348;
  --border: #334155;
  --text2: #cbd5e1;
  --muted: #94a3b8;
  --muted2: #64748b;
  --accent: #818cf8;
  --accent-h: #a5b4fc;
  --accent-lt: #1e1b4b;
  --header-bg: rgba(15, 23, 42, 0.85);
  --dropdown-bg: #1e293b;
  --footer-bg: #020617;
}
header {
  position: sticky;
  top: 0;
  z-index: 10000;
  isolation: isolate;
  overflow: visible;
  background: var(--header-bg);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 1px 0 var(--border);
  transition: background 0.25s ease, border-color 0.25s ease;
}
header nav.container {
  max-width: min(var(--content-max, 1180px), 100%);
  margin: 0 auto;
  padding: 0 clamp(16px, 3vw, 28px);
}
nav.site-nav,
nav.container.site-nav {
  display: flex;
  align-items: center;
  height: 68px;
  gap: 32px;
  column-gap: 32px;
  overflow: visible;
}
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  margin-right: 24px;
}
.logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, #4f46e5, #06b6d4);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.3);
}
.logo-icon svg {
  width: 20px;
  height: 20px;
}
.logo-text {
  font-family: "DM Sans", sans-serif;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text, #0f172a);
  line-height: 1.2;
}
.logo-text .brand-all {
  color: var(--accent);
}
.logo-text .brand-domain {
  display: block;
  font-size: 0.62rem;
  font-weight: 500;
  color: var(--muted);
}
.nav-links {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 2px;
  flex: 1;
  overflow: visible;
}
.nav-item {
  position: relative;
  overflow: visible;
}
.nav-link {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--muted);
  padding: 8px 13px;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.18s, color 0.18s;
  white-space: nowrap;
  background: none;
  border: none;
  font-family: "DM Sans", sans-serif;
}
.nav-link:hover,
.nav-item:hover .nav-link,
.nav-link.active,
.nav-item.active-section > .nav-link {
  background: var(--accent-lt);
  color: var(--accent);
}
.nav-link svg {
  width: 11px;
  height: 11px;
  transition: transform 0.2s;
  flex-shrink: 0;
}
.nav-item:hover .nav-link svg {
  transform: rotate(180deg);
}
.nav-dropdown {
  display: none;
  position: absolute;
  top: calc(100% + 6px);
  left: 0;
  background: var(--dropdown-bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: 0 16px 48px rgba(79, 70, 229, 0.16);
  min-width: 220px;
  padding: 8px 8px 4px;
  z-index: 10001;
  max-height: min(75vh, calc(100dvh - 100px));
  overflow-x: visible;
  overflow-y: auto;
  overscroll-behavior: contain;
  -webkit-overflow-scrolling: touch;
}
/* Invisible hit-area bridge: removes hover flicker in the gap below the trigger */
.nav-dropdown::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -6px;
  height: 6px;
}
.nav-item:hover .nav-dropdown,
.nav-item:focus-within .nav-dropdown {
  display: block;
  animation: siteDdFade 0.15s ease;
}
.nav-item:hover .nav-dropdown.dd-grid:not(.dd-grid-wide),
.nav-item:focus-within .nav-dropdown.dd-grid:not(.dd-grid-wide) {
  display: block !important;
}

.nav-item:hover .nav-dropdown.dd-grid.dd-grid-wide,
.nav-item:focus-within .nav-dropdown.dd-grid.dd-grid-wide {
  display: grid !important;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  grid-auto-rows: min-content;
  align-content: start;
}
/* Wide utility menu: align to trigger’s right edge so it stays in the viewport */
.nav-links > .nav-item:nth-child(3) .nav-dropdown {
  left: auto;
  right: 0;
}
/* Wider utility mega-menu (replaces inline min-width) */
.nav-dropdown.dd-grid.dd-grid-wide {
  min-width: 460px;
}
.dd-header.dd-header--spaced {
  margin-top: 8px;
}
.dd-all.dd-all--full-span {
  grid-column: 1 / -1;
}
@keyframes siteDdFade {
  from {
    opacity: 0;
    transform: translateY(-6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.dd-header {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted2);
  padding: 6px 12px 4px;
  margin-bottom: 2px;
}
.dd-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-radius: 8px;
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--text2);
  transition: background 0.15s, color 0.15s;
  cursor: pointer;
}
.dd-link:hover,
.dd-link.active {
  background: var(--accent-lt);
  color: var(--accent);
}
.dd-link-icon {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.95rem;
  flex-shrink: 0;
}
.dd-all {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 8px;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent);
  border-top: 1px solid var(--border);
  margin-top: 0;
  border-radius: 0 0 10px 10px;
  transition: background 0.15s;
}
.dd-all:hover {
  background: var(--accent-lt);
}
.nav-search-wrap {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
  position: relative;
}
.nav-search {
  display: flex;
  align-items: center;
  background: var(--surface2);
  border: 1.5px solid var(--border);
  border-radius: 100px;
  padding: 0 14px;
  gap: 8px;
  height: 38px;
  width: 230px;
  transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
}
.nav-search:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
  background: var(--dropdown-bg);
  width: 270px;
}
.nav-search svg {
  width: 14px;
  height: 14px;
  color: var(--muted2);
  flex-shrink: 0;
}
.nav-search input {
  background: none;
  border: none;
  outline: none;
  font-family: "DM Sans", sans-serif;
  font-size: 0.84rem;
  color: var(--text, #0f172a);
  width: 100%;
}
.nav-search input::placeholder {
  color: var(--muted2);
}
.nav-search-results {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 320px;
  background: var(--dropdown-bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: 0 16px 48px rgba(79, 70, 229, 0.16);
  padding: 8px;
  z-index: 10002;
  max-height: 380px;
  overflow-y: auto;
}
.nav-search-results.show {
  display: block;
  animation: siteDdFade 0.15s ease;
}
.nav-search-results::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: -8px;
  height: 8px;
}
.sr-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.15s;
  text-decoration: none;
  color: var(--text2);
}
.sr-item:hover {
  background: var(--accent-lt);
  color: var(--accent);
}
.sr-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  flex-shrink: 0;
}
.sr-info {
  flex: 1;
  min-width: 0;
}
.sr-name {
  font-size: 0.86rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sr-cat {
  font-size: 0.72rem;
  color: var(--muted2);
}
.sr-empty {
  padding: 16px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--muted);
}
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  margin-left: 12px;
}
.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text2);
  border-radius: 2px;
  transition: all 0.3s;
}
.hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.hamburger.open span:nth-child(2) {
  opacity: 0;
}
.hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}
.mobile-menu {
  display: none;
  position: fixed;
  top: 68px;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--dropdown-bg);
  z-index: 9990;
  overflow-y: auto;
  padding: 20px;
  border-top: 1px solid var(--border);
}
.mobile-menu.open {
  display: block;
  animation: siteSlideDown 0.25s ease;
}
@keyframes siteSlideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
.mobile-search {
  display: flex;
  align-items: center;
  background: var(--surface2);
  border: 1.5px solid var(--border);
  border-radius: 100px;
  padding: 0 16px;
  gap: 8px;
  height: 44px;
  margin-bottom: 20px;
}
.mobile-search:focus-within {
  border-color: var(--accent);
  background: var(--dropdown-bg);
}
.mobile-search svg {
  width: 16px;
  height: 16px;
  color: var(--muted2);
}
.mobile-search input {
  background: none;
  border: none;
  outline: none;
  font-family: "DM Sans", sans-serif;
  font-size: 0.9rem;
  color: var(--text, #0f172a);
  width: 100%;
}
.mobile-cat {
  margin-bottom: 20px;
}
.mobile-cat-title {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted2);
  padding: 0 4px;
  margin-bottom: 8px;
}
.mobile-cat-links {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.mobile-link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--text2);
  transition: all 0.15s;
}
.mobile-link:hover,
.mobile-link:active {
  background: var(--accent-lt);
  border-color: #c7d2fe;
  color: var(--accent);
}
.mobile-link span:first-child {
  font-size: 1rem;
}
/* BMI in-page anchor strip */
.bmi-subnav-outer {
  border-bottom: 1px solid var(--border);
  background: var(--header-bg);
}
.page-anchor-nav {
  padding: 10px 0;
  font-size: 0.82rem;
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  align-items: center;
}
.page-anchor-nav a {
  color: var(--muted);
  font-weight: 500;
}
.page-anchor-nav a:hover {
  color: var(--accent);
}
/* Site footer — compact dark rail (shared index + calculator pages) */
footer.site-footer {
  background: #0f172a;
  border-top: 1px solid #1e293b;
  padding: 52px 0 32px;
}
:root[data-theme="dark"] footer.site-footer {
  background: #0f172a;
}
footer.site-footer .foot-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(16px, 3vw, 48px);
}
footer.site-footer .foot-top {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  padding-bottom: 40px;
  border-bottom: 1px solid #1e293b;
  margin-bottom: 24px;
}
.foot-brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-width: 0;
}
.foot-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 0;
}
.foot-logo-icon {
  width: 34px;
  height: 34px;
  flex-shrink: 0;
  background: linear-gradient(135deg, #4f46e5, #06b6d4);
  border-radius: 9px;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.28);
}
.foot-logo-icon svg {
  width: 17px;
  height: 17px;
}
.foot-logo-text {
  font-family: "DM Sans", sans-serif;
  font-weight: 700;
  font-size: 0.95rem;
  color: #f1f5f9;
  line-height: 1.25;
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}
.foot-logo-text .brand-all {
  color: #a5b4fc;
}
.foot-logo-domain {
  font-size: 0.65rem;
  font-weight: 500;
  color: #475569;
}
.foot-tagline {
  font-size: 0.72rem;
  color: #475569;
  line-height: 1.55;
  margin: 0;
  margin-top: 14px;
  max-width: 320px;
}
.foot-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}
.foot-badge {
  font-size: 0.62rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #64748b;
  border: 1px solid #1e293b;
  padding: 4px 10px;
  border-radius: 999px;
}
.foot-col {
  min-width: 0;
}
.foot-col-head {
  font-family: "DM Sans", sans-serif;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: #f1f5f9;
  margin: 0 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid #1e293b;
}
.foot-col ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
.foot-col li {
  margin: 0;
  padding: 0;
}
footer.site-footer a.foot-link {
  text-decoration: none;
}
.foot-link {
  display: block;
  font-size: 0.82rem;
  color: #94a3b8;
  line-height: 1;
  padding: 5px 0;
  text-decoration: none;
  border: none;
  transition: color 0.15s ease;
}
footer.site-footer a.foot-link:hover {
  color: #ffffff;
  text-decoration: none;
}
.foot-link::after {
  content: " →";
  opacity: 0;
  transition: opacity 0.15s ease;
}
.foot-link:hover::after {
  opacity: 1;
}
.foot-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px 24px;
  font-size: 0.75rem;
  color: #475569;
  padding: 0;
  margin: 0;
  border: none;
}
.foot-bottom-left,
.foot-bottom-right {
  margin: 0;
}
/* Tablet: brand row full width; categories 2×2 */
@media (min-width: 768px) and (max-width: 1023px) {
  footer.site-footer .foot-top {
    grid-template-columns: 1fr 1fr;
    column-gap: 40px;
    row-gap: 28px;
  }
  footer.site-footer .foot-brand {
    grid-column: 1 / -1;
    align-items: center;
    text-align: center;
  }
  footer.site-footer .foot-logo {
    justify-content: center;
  }
  footer.site-footer .foot-tagline {
    margin-left: auto;
    margin-right: auto;
  }
  footer.site-footer .foot-badges {
    justify-content: center;
  }
  footer.site-footer .foot-col:nth-child(2) {
    grid-column: 1;
    grid-row: 2;
  }
  footer.site-footer .foot-col:nth-child(3) {
    grid-column: 1;
    grid-row: 3;
  }
  footer.site-footer .foot-col:nth-child(4) {
    grid-column: 2;
    grid-row: 2;
    align-self: start;
  }
  footer.site-footer .foot-col:nth-child(5) {
    grid-column: 2;
    grid-row: 3;
    align-self: start;
  }
}
/* Desktop: five columns */
@media (min-width: 1024px) {
  footer.site-footer .foot-top {
    grid-template-columns: 1.4fr repeat(4, 1fr);
    gap: 40px;
    align-items: start;
  }
  footer.site-footer .foot-brand {
    min-height: 100%;
  }
}
/* Mobile: centered brand; categories 2-col; compact bottom bar */
@media (max-width: 767px) {
  footer.site-footer .foot-top {
    grid-template-columns: 1fr 1fr;
    column-gap: 20px;
    row-gap: 24px;
  }
  footer.site-footer .foot-brand {
    grid-column: 1 / -1;
    align-items: center;
    text-align: center;
  }
  footer.site-footer .foot-logo {
    justify-content: center;
  }
  footer.site-footer .foot-tagline {
    margin-left: auto;
    margin-right: auto;
  }
  footer.site-footer .foot-badges {
    justify-content: center;
  }
  footer.site-footer .foot-col:nth-child(2) {
    grid-column: 1;
    grid-row: 2;
  }
  footer.site-footer .foot-col:nth-child(3) {
    grid-column: 1;
    grid-row: 3;
  }
  footer.site-footer .foot-col:nth-child(4) {
    grid-column: 2;
    grid-row: 2;
    align-self: start;
  }
  footer.site-footer .foot-col:nth-child(5) {
    grid-column: 2;
    grid-row: 3;
    align-self: start;
  }
  footer.site-footer .foot-bottom {
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
  }
}

@media (max-width: 900px) {
  .nav-links {
    display: none;
  }
  .nav-search {
    display: none;
  }
  .hamburger {
    display: flex;
  }
}
@media (max-width: 480px) {
  .mobile-cat-links {
    grid-template-columns: 1fr;
  }
}

/* ===== THEME TOGGLE BUTTON =====
   Fallback values are inlined in every var() so the button always renders
   even on pages where shared CSS variables haven't been defined yet. */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  padding: 0;
  border-radius: 999px;
  background: var(--surface2, #f0f3fc);
  border: 1.5px solid var(--border, #e2e7f5);
  cursor: pointer;
  color: var(--text2, #334155);
  position: relative;
  overflow: hidden;
  transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease, transform 0.2s ease;
  flex-shrink: 0;
  font: inherit;
  line-height: 1;
}
.theme-toggle:hover {
  border-color: #c7d2fe;
  color: var(--accent, #4f46e5);
  background: var(--accent-lt, #eef2ff);
  transform: translateY(-1px);
}
:root[data-theme="dark"] .theme-toggle:hover {
  border-color: var(--accent, #818cf8);
}
.theme-toggle:focus-visible {
  outline: none;
  border-color: var(--accent, #4f46e5);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.18);
}
.theme-toggle svg {
  width: 18px;
  height: 18px;
  position: absolute;
  top: 50%;
  left: 50%;
  margin: -9px 0 0 -9px;
  transition: transform 0.45s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.25s ease;
}
.theme-toggle .icon-sun {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}
.theme-toggle .icon-moon {
  opacity: 0;
  transform: rotate(-90deg) scale(0.4);
}
:root[data-theme="dark"] .theme-toggle .icon-sun {
  opacity: 0;
  transform: rotate(90deg) scale(0.4);
}
:root[data-theme="dark"] .theme-toggle .icon-moon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}
/* Adapt size in different header layouts */
.nav-actions .theme-toggle {
  width: 42px;
  height: 42px;
}
.nav-actions .theme-toggle svg {
  width: 18px;
  height: 18px;
}

/* Mobile menu overlay tweaks for dark mode */
:root[data-theme="dark"] .mobile-link {
  background: var(--surface2);
  border-color: var(--border);
  color: var(--text2);
}
:root[data-theme="dark"] .mobile-link:hover,
:root[data-theme="dark"] .mobile-link:active {
  background: var(--accent-lt);
  border-color: var(--accent);
  color: var(--accent-h);
}
:root[data-theme="dark"] .nav-search input,
:root[data-theme="dark"] .mobile-search input {
  color: var(--text);
}